This application is a 371 of PCT/H092/00035, filed Sep. 11, 1992.
The present invention relates to a puncture needle device, mainly for a closed system introduction of a catheter into a blood vessel, consisting of a needle and a body. The device can also be used for introducing pacemaker electrodes, guide wires or the like.
Haemodialysis, blood transfusion and replacement, or parenteral nutrition of patients in serious condition is generally carried out through catheters introduced into a central vein of the patient. Especially important is an appropriate indroduction of-such catheters into the great veins near to the heart of the patient, during permanent administration of drugs, nutritional fluids, blood etc.
Catheters may be punctured into a blood vessel in different ways.
When applying a so called Branule-type device, the catheter surrounds the puncture needle as a sleeve and the needle introduced into the blood vessel is guiding said sleeve which is then also introduced into the blood vessel. Finally, the needle is pulled out of the catheter.
This method of puncturing can only be applied in a sterilized room as the introduction of the catheter is carried out in an open wound.
Another known method is the so-called Seldinger-method, wherein the syringe is removed from the needle after it has been punctured into the vein and a guiding wire is introduced into the vein through the passage of the needle. Thereafter, the needle is removed from the wire and the catheter is introduced into the vein guided by the same wire.
The advantage of this method is that a rather thick catheter can be introduced into a relatively small opening on the vein. The drawback is however, that the system is opened by removing the syringe and, accordingly, there is a growing danger of infection.
Furthermore, the point of the needle often slips out of the vein during removing the syringe and introducing the wire, which can cause additional injuries. Extravasations can also occure, wich make diffucult or even impossible to carry out further punctures.
Yet another method is known, wherein a relativly thick needle is punctured into the blood vessel and the catheter is introduced directly through the passage of the needle, after the syringe has been removed. Thereafter, the needle is pulled out of the vein and removed from the catheter (which is possible only if there is no flange at the end of the catheter).
Disadvantage of this method is that the system becomes opened when the syringe is removed and that the point of the needle easily slips out of the vein, as it has been explained in connection with the Seldinger-method.
The weak point of all the known methods is the difficulty of introduction of the catheter. Due to this, the puncture needle may accidently be pulled out and infection would be a real danger in such an open system. Generally, the danger of pulling out the needle is about 20-30%, even if it is used by a skilled person.
Another problem is fixing the outer end of the catheter. For this purpose catheter holders made of several parts are generally used (see e.g. U.S. Pat. No. 4,149,535). The use of such catheter holders is generally rather difficult, because all the parts should be mounted at the end of the catheter.